This invention discloses a lifting jack and adaptor combination for use in lifting and lowering a piston rod, such as a connecting rod or master rod, clear of the crankshaft journal of an industrial engine in a safe and novel manner. Lifting jacks are well known in the prior art and are hydraulically, pneumatically, or mechanically actuated. The present invention is used in combination with a lifting jack for positive engagement with the end of the piston rod after the rod cap has been removed therefrom. This enables the piston rod to be positively controlled and elevated to a sufficient height to enable the crankshaft piston rod bearing to be removed and replaced.
The master rod of a large industrial engine is extremely heavy and cannot safely be lifted and held elevated by one man. In the past, various levers and pry bars have been used for forcing the rod end, along with the piston, away from the crankshaft journal and consequently there is always the danger that the heavy piston and rod will slip and the rod end fall and mangle or sever the mechanic's hand. The present invention overcomes this unsafe practice by the combination of a special adaptor and lifting jack made especially for engaging and lifting the end of the piston rod in a new and unobvious manner. The term "piston rod", as claimed herein includes the master rod as well as the piston rod of a large industrial internal combustion engine of the reciprocating type.